Polyester dye with dye in methylene chloride and a chlorofluoroalkane

ABSTRACT

Process for the dyeing of synthetic textile materials, by treating said textile material with a dyebath consisting of a solution or dispersion of an organic dyestuff in a halogenated methane or ethane derivative of the general formula

United States Patent [1 van der Eltz et al.

[ 1 Oct. 30, 1973 POLYESTER DYE WITH DYE IN METHYLENE CHLORIDE AND ACHLOROFLUOROALKANE Inventors: Hans-Ulrich van der Eltz; Walter Birke,both of Frankfurt, Main; Wolfgang Kunze, Hofheim, Taunus; Franz Schiin,Frankfurt, Main, all of Germany Farbwerke Hoecht Aktiengesellschaft,Frankfurt, Main, Germany Filed: Jan. 18, 1972 Appl. No.: 107,587

Assignee:

Foreign Application Priority Data Jan, 20, 1970 Germany P 20 02 286.0

US. Cl. 8/175, 8/41 A, 8/41 B,

8/41 C, 8/169, 8/176 Int. Cl D06p l/68 Field of Search 8/94, 175, 142

References Cited UNITED STATES PATENTS 4/1964 Castle 8/94 3,473,1759/1965 Sieber 68/18 R 3,081,140 3/1963 Ford 3,105,769 10/1963 Elleren8/142 Primary Examiner-Donald Levy Attorney-Curtis, Morris & Safford inwhich R represents the radical of the formula FCl C-CFCl, Cl C, Cl HC orF ClC-CFCl-, or in a preferably azeotropic mixture of said halogenatedsolvent with an alcohol, ester, ketone and/or a halogenated hydrocarbon,and then fixing the dyestuff on the textile material by the action ofheat.

8 Claims, No Drawings POLYESTER DYE WITH DY-E IN METHYLENE CHLORIDE ANDA CHLOROFLUOROALKANE is due to the fact that the water absorbedby thetextile material has first tobe brought to the vaporization temperatureof water, which requires aconsiderable amount of energy owing to thehigh specific heat of water (l kcal per kg of water per degreeCentigrade of rise of temperature). A substantially higher energy amounthas then to be applied for vaporizing the water at 100C about 539' kcalper kg of water at 100C). All these drying operations, moreover, implythe risk that both the textile material and the dyestuffs are adverselyaffected by the action of heat. In practice, drying has, therefore, tobe effected relatively carefully, and a necessary consequence thereof isa low processing speed of the textile material. Another detrimentalresult of the drying operation is the migration of the dyestuffs.Besides this, the aqueous bath remaining after dyeing still contains asubstantial amount of unconsumed dyestuffs and adjuvants which causeconsiderable difficulties and additional technical expense in thenecessary removal of waste water.

It has, therefore, already been proposed to dye from organic liquids,for example esters, such as ethyl acetate; ethers, such as diisopropylether; hydrocarbons, such as benzene, and halogenated hydrocarbons, suchas perchloro ethylene, trichloro-ethane, carbon tetrachloride,chloroform and trichloro-ethylene (cf. German Offenlegungsschrift No. l914 055 Some of these solvents are, however, inflammable and sometimestheir vapors are explosive. Moreover, some of these solvents have adamaging effect on the fibers and on the dyestuffs, and what is more,the major part of the solvents hitherto used is rather poisonous. It is,therefore, absolutely necessary to operate in explosionproo'f plantsand/or to take expensive technical precautions in order to preventinjuries to health by solvent vapors. I

It has now been found that fast dyeings are obtained on synthetictextile materials in a very simple and economic manner by treating saidtextile material with solutions or dispersions of organic dyestuffs inhalogev nated methane or ethane derivatives of the general formula inwhich R is a group of the formula FCl CCFCl, Cl C-,Cl HC or F ClCCFCl,and then fixing the dyestuffs on the textile material by the action ofheat.

According to the process of the invention, the abovementionedhalogenated solvents, i.e., 1,2,2-tr'ifluorotrichloro-ethane,monofluoro-trichloro-methane, monofluoro-dichloro-methane and l ,1,2,2-tetrafluorodichloro-ethane, are preferably used in the form of puresubstances. Among these solvents, trifluorotrichloro-ethane andmonofluoro-trichloro methane are generally preferred. In some cases, itis also advantageous to use the above-cited halogenated solvents inadmixture with other organic solvents, especially with alcohols, esters,ketones and halogenated hydrocar-- bons. Examples of such secondarysolvents are especially methanol, ethanol, ethers of glycols, forexample, diethylene-glycol monobutyl ether and methylene chloride. Incase mixtures of solvents are used, a weight ratio of from 50 to 99%,preferably to 99%, of the halogenatedmethane or ethane derivatives to l50%, preferablyl 15%, of the other organic solvents is chosen. Ifsecondary solvents are used, preferably such compounds areselected'which result together with the halogenated solvents asazeotropic mixtures since they behave as uniform substances both in theliquid and in the vapor phases. Hence, there is no decrease in theamount of one of the components during the dyeing operation and therecovering of the solvent. The use of the foregoing solvent mixtures,preferably azeotropic mixtures, is especially advantageous for suchcases in which the dyestuff to be applied is only unsatisfactorilysoluble in halogenated methane or ethane derivatives alone. Azeotropicmixtures are preferably used in the case ofl,2,2-trifluoro-trichloro-ethane since there it is possible to benefitfrom the resulting boiling point depression and also to use solventswhich, as such, are inflammable but in the azeotropic mixture are not.Examples of such azeotropic mixtures are mixtures consisting of1,2,2-trifluoro-trichloro-ethane and methanol (6% by weight of methanol,boiling point 399C at 760 mm Hg), acetone (12.5% by weight of acetone,boiling point 45C at 760 mm Hg), methylene chloride (49.5% by weight ofmethylene chloride, boiling point 37 C at 760 mm Hg) and chloroform(7.2% by weight of chloroform, boiling point 47.4C at 760 mm Hg).

As synthetic textile material to be dyed there is especially mentionedmaterial made from polyesters, above all, polyethylene-glycolterephthalate, polyamides, polypropylene, polyacrylonitrile, polyvinylchloride, cellulose-2 v-acetate and cellulose-tri-acetate. Theabove-mentioned textile materials may also be blended with other fibrousmaterials, especially with cellulose fibers or wool; such articles are,for example, mixed fabrics composed of polyethylene-glycol terephthalateand cotton or polyethylene-terephthalate and wool. The syntheticmaterial may be available for dyeing in a variety of forms, for example,combed material, cables, filaments, woven and knit fabrics. Films,sheets and fleeces may also be colored according to the process of theinvention.

The dyestuffs to be used for the process of the invention are organicdyestuffs which can be dissolved or dispersed in the above-mentionedsolvents or mixtures of solvents and which are absorbed by the syntheticfibrous material during the subsequent heat treatment, especiallydisperse dyestuffs that have hitherto been used for the dyeing of theabove-cited synthetic materials from aqueous media. Moreover, dyestuffswhich cannot be applied from aqueous media or which provide onlyunsatisfactory results according to the conventional method, may nowalso be employed, especially those known as oilor alcohol-solubledyestuffs. The dyestuffs suitable for the present invention may belongto different classes of compounds, for example azo dyestuffs, especiallymonoand disazo dyestuffs, polyazo dyestuffs, dyestuffs of theanthraquinone series, nitro dyestuffs, dyestuffs of the quinophthaloneseries, such as 3-hydroxy-quinophthalone or 4-bromo-3-hydroxy-quinophthalone, indigoid dyestuffs as well as components ofazo dyestuffs which produce the final azo dyestuff on the fiber bycoupling, furthermore perinone, oxazine, nitroso, stilbene,benzothioxanthene and benzoxanthene dyestuffs. Finally, metal complexdyestuffs of the azo series may also be used as far as they can can bedissolved or dispersed in the abovementioned solvents or mixtures ofsolvents.

If the syestuffs are soluble in the solvents used, it is generally notnecessary to add adjuvants. If they are not or are only sparinglysoluble, the addition of a suitable dispersing agent that promotesand/or stabilizes fine distribution is advantageous. The addition of atenside is also advantageous if it should be difficult for the dye topenetrate heavy-weight and tightly woven materials. Tensides of thistype are especially oxalkylated, in particular oxethylated, fattyalcohols or fatty acids, alkylpolyglycol ethers, aryl-polyglycol ethersand/or alkylaryl-polyglycol ethers or the sulfonates thereof. Thesetensides are generally added in an amount of from about 0.1 to 5%,preferably from 0.5 to 1%, calculated on the weight of the solvent.

The process of the invention may be carried out batchwise orcontinuously, the continuous operation being preferred. The material tobe dyed is treated with the organic dyebath in known manner by padding,for example, on a foulard machine, slop-padding or spraying. Thetemperature applied during this operation has practically no influenceon the dyeing result; it is generally within the range of from about to60C, preferably room temperature. If treatment of the goods with theliquor is carried out at a temperature above the boiling point of thesolvent or mixture of solvents, this operation is performed in apressure-resistant dyeing apparatus under the pressure establishingitself in each case. Finally, dyestuff application may also be carriedout at the boiling point of the solvent, and the vapors of the solventresulting in this proceeding are then condensed by a suitable refluxdevice and recycled continuously to the dyeing apparatus.

After its treatment with the dyeing liquor the textile material is, ifnecessary, squeezed to the desired content of impregnation solution offrom about 50 to 150%, advantageously about 70 to 90%, calculated on thedry weight of the fibrous material.

The dyestuff amount in the solution or dispersion comprising the dyebathis generally from about 0.001 to 5% by weight and depends, especially,on the color intensity desired, on the material to be dyed or on thedyestuff used. The optimum amount to be used can easily be determinedfor each individual case by means of corresponding preliminary tests.

The textile material treated with the dyebath is then preferably dried,for example, by hot air, an inert gas such as nitrogen or air, that isdrown through the material, or by a moderate heating with infraredradiation. The solvent vapors formed are again liquified in suitabledevices by cooling or compression and cooling. The recovered solventsare then available again for the dyeing process. Thus, it is possibleaccording to the invention to operate with a limited amount of solvents.Where required, slight losses that cannot be avoided in any case arecompensated for by feeding in fresh solvent.

The dyestuffs thus applied are fixed onthe textile material by theaction of heat in a manner usual for each individual synthetic material,generally at a temperature of from about 100 to 240C.

Said heat treatment can be performed with superheated steam or vapors oforganic solvents at a temperature of from about to C. Fixing can also beperformed in melts made from molten metals, paraffins, waxes,oxalkylation products of alcohols or fatty acids or in eutectic mixturesof salts at temperatures of from about 100 to 220C. Preferably, dyestufffixation is carried out by means of dry heat, i.e., according to theso-called Thermosol process, at about to 220C. The fixation temperatureto be applied depends, especially, on the textile material to be dyed.

Although the textile material is preferably dried as mentioned aboveprior to fixing, it is also possible to perform the drying operation andthe thermal treatment in a single step.

An after-treatment of the dyeings obtained according to the invention isgenerally not necessary but, when tensides have additionally been used,such an aftertreatment of the textile material may be advantageous andis suitable performed by washing the material once more with the solventor solvent mixture already used in the dyeing operation. Of course,another methane or ethane derivative of the aforementioned formula mayalso be used for this purpose. A reductive aftertreatment for theelimination of unfixed dyestuff, as generally necessary in conventionalprocesses, is not required for the process of the invention, except inspecial cases.

The dyeings obtainable according to the claimed process have at leastthe same fastness properties as dyeings produced from aqueous mediaaccording to the conventional method have.

The technical advantage of this invention over the prior art techniqueusing aqueous dyebaths resides, especially, in the fact that asubstantially lower energy amount is required for the drying operationthan with the usual dyeing methods from aqueous media. For example, thespecific heat of methane and ethane derivatives used according to theinvention amounts to about 0.2 0.25 kcal per kg per degree centigradewhereas, in comparison thereto, water has a specific heat of l kcal perkg per degree centigrade. Thus, in order to heat the dyeing medium toits boiling point, only a fraction of the heat amount needed for "wateris required according to the invention and, moreover, the liquids usedin the claimed process have substantially lower boiling points thanwater. Above all, the energy amount of be applied for the vaporizationof the dyeing liquid is substantially smaller according to the inventionthan according to the conventional method. In order to varporize 1 kg ofwater at the boiling point, about 539 kcal have to be spent, whereas theheat of vaporization at the boiling point of the solvents of the aboveformula is from about 33 to 58 kcal per kg. Hence, the energyconsumption according-to the invention is only a fraction of that to bespent for the drying operation according to the dyeing process fromaqueous media. Moreover, due to the favorable energy balance, it ispossible to use in the claimed process drying devices of a simpler typeand, since drying can be performed substantially quicker than with theconventional process, the processing speed of the goods is substantiallyhigher. Another very substantial advantage of the invention is thatthere are no difficulties involved wiJh waste water purification.Furthermore, according to the invdntion, almost no corrosion is observedon the dyeing machines as it is when water is used. Another advantage isthe successful use of dyestuffs that could not be used for the dyeingfrom aqueous media or which provided only unsatisfactory results. I 7

When dyeing from an aqueous bath, most of the dyestuffs have to beapplied in the form of preparations since the crude dyestuff yields onlypoor results. According to the process of the invention, however,dyestuffs that are soluble in the solvents used can be applied withoutany pre-treatment or any additive.

In comparison to known processes in which also organic solvents areused, the process of the invention has the advantage that the solventsor solvent mixtures used are not inflammable and almost not poisonous.For example, the MAK-values (maximum allowable concentration ofindustrial atmospheric contaminants at the work place) of theabove-cited methane or ethane derivatives are about'l ,000 ppm (cf.Ullmanns Encyklopaedie der technischen Chemie, Vol. 2/2 (1968) pages 620to 624; cf. also Threshold Limit Values). In contradistinction thereto,the organic solvents-used in the known processes are inflammable and/orthey are comparatively strong poison having MAK-values of 100 ppm and,in many cases, even less. For example, benzene has a MAK-value of 25 ppmand carbon tetrachloride only of 10 ppm. Furthermore, the solvents usedaccording to the invention have a substantially lower surface tensionthan the solvents hitherto used for the same purpose, and therefore thetextile material is much better wetted in the dyebath. Hence, thedyeings obtained, although produced with the same dyestuff amount, havea far greater color intensity than the dyeings obtained by the knownprocess. In contrast to the known process, the use of theabove-mentioned solvents or solvent mixtures does not damage the fibers.

The devices mentioned in the following Examples are closed ones so thatno vapors of solvents can escape. If the dyeing temperature is above theboiling point of the solvent or solvent mixture used, the treatment isperformed in pressure-resistant dyeing apparatuses under the pressurethat establishs itself in each case. Although not referred toparticularly in the following Examples, the solvent vapors formed duringthe drying operation are condensed and recovered by cooling or bycompression and cooling. The solvents thus recovered can then be usedagain. The Colour Index Numbers referred to in the Examples relate toColour Index, Volume IIl, 2nd edition (1956); the percentages indicatingthe squeezing effect are by weight of the dry fibrous material.

The following Examples serve to illustrate the invention.

E X A M P L E 1 Three Grams of the dyestuff of the formula (C.l. No.26105 Solvent Red 24) were dissolved in 1 liter oftrichloro-fluoromethane at about 20C. A mixed fabric composed ofpolyester fibers and wool was padded with this dyestuff solution on afoulard machine at the cited temperature, with a squeezing effect ofSubsequently, the fabric was dried at room temperature by yaporizationof the solvent. The dyestuff was then fixed by means of a thermosoltreatment for 45 seconds at 190C. An intense red dyeing on the polyesterportion of the fibre blend was obtained. A reductive after-treatment ofthe dyeing was not required.

E X-A M P L E 2 Three Grams of the dyestuff of the formula (C.I. No.11360 Solvent Brown 3) were pasted up with 10 cc. of diethylene-glycolmonobutyl ether and then this paste was diluted to 1 liter withtrichlorofluoromethane at about 20C. A fabric made from texturizedpolyester fibers was padded with this bath at a squeezing effect of 80%.The fabric was dried by drawing off the solvent vapors in an appropri-'ate apparatus. Subsequently, the material was thermosoled for 30 secondsat C for fixing the dyestuff. An orange brown dyeing was obtained.

EXAMPLES Two Grams of the dyestuff of the formula EXAMP'LE4 Twenty Gramsof the commercial disperse dyestuff of the formula were dispersed in 1liter of trichloro-fluoromethane at about 15C. A blended fabric madefrom polyester fibers and cotton was padded with this dyestuffdispersion at room temperature. The fabric was dried by drawing off thesolvent in an appropriate apparatus.

Subsequently, the dyestuff was fixed on the fabric by a thermosoltreatment for 1 minute at 200C. A red dyeing on the polyester portion ofthe blend was obtained.

EXAMPLES Five Grams of the commercial disperse dyestuff of the formulawere pasted up with 40 ml of benzoic acid methyl ester and stirred into960 ml of trichloro-fluoromethane at about 20C. A fabric made frompolyester fibers was impregnated with this padding liquor and treatedfur-' ther as disclosed in Example 4. An orange dyeing ,was obtained.

E X A M P L E 6 Three Grams of the disperse dyestuff of the formulaCHz-CHz-OH were pasted up with 30 ml of diethylene-glycol monobutylether. Subsequently, the mixture was diluted to 1 liter withtrichloro-fluoromethane at about 20C. A polyester fabric was padded withthis bath and treated further as disclosed in Example 4. A brown dyeingwas obtained.

EXAMPLE7 Ten Grams of the commercial disperse dyestuff of the formula.lIzN )(l)\ (1)11 I Br l 110 NH:

were dispersed in 1 liter of l,2,2-trifluoro-trichloroethane at about30C. A fabric made from polyester fibers was padded with this bath on afoulard machine. The material was then dried by drawing off the solventvapors in vacuo by means of an appropriate apparatus. Subsequently, thedyestuff was fixed on the fiber by a thermosol treatment for 1 minute at190C. A blue dyeing was obtained.

E x A M P L E 8 Three Grams of the dyestuff of the formula ple 7. Abrown dyeing was obtained.

E X A M PL E 9 Two Grams of the dyestuff of the formula (C.I. No. 12700Solvent Yellow 16) were dissolved at about 25C in 1 liter of1,2,2-trifluoro-trichloro-ethane. A fabric made from texturizedpolyester fibers was padded with this dyestuff solution. The fabric wasdried by drawing off the solvent vapors under reduced pressure.Subsequently, the dyeing was finished by a thermosol treatment for 40seconds at C. A yellow dyeing was obtained.

E X A M P L E 10 Five Grams of the dyestuff of the formula (C.I. No.12055 Solvent Yellow 14) were dissolved at about 25C in 1 liter of anazeotropic mixture consisting of 94% of l,2,2-trifu1oro-trichloroethaneand 6% of methanol. This solution was then applied by padding on afoulard machine to a blended fabric made from polyester fibers andcotton. Half of the impregnated blended fabric was dried under reducedpressure. The other half of the fabric was dried with hot air of 40C ona conventional drying device. Subsequently, both halves were thermosoledfor 45 seconds at C, for fixing the dyestuff. In both cases, orange reddyeings were obtained.

E X A M P L E l 1 Two Grams of the dyestuff of the formula J Qt;

(C.I. No. 26150 Solvent Black 3) were dissolved at about 30C in 1 literof an azeotropic mixture consisting of 94% ofl,2,2-trifluoro-trichloroethane and 6% of methanol. A fabric made frompolyester fibers was padded with this bath. Drying and after-treatmentof the fabric were performed as disclosed in Example 10. A grey dyeingwas obtained. E x A M P L E 15 2.5 Grams of the disperse dyestuff of theformula E X A M P L E 12 Three Grams of the dyestuff of the formula CHzU1b O11 N=N N CH -CHz-OH (3H3 ClHa H0 01 were dissolved in 40 ml ofdiethylene-glycol monobutyl ether and the solution was then diluted to 1liter with trichloro-fluoromethane at about 20C. A polyamide- 6,6 fabricwas impregnated with this padding liquor on a foulard machine, thendried with hot air of about 40C in a drying device and thermosoled for30 seconds (C.l. No. 26105 Solvent Red 24) o were dissolved at about Cin 1 liter of trichloroat 190 A red rown dyeing was obtained.fluoro-methane. A combed material made from poly- E X A M P L E 16propylene fibers i padded wlth .thlspyestuff Solutlon Ten Grams of thecommercial disperse dyestuff of on a foulard machine and then dried inthe air. Subsethe formula quently, the dyestuff was fixed for 30 secondsat 140C 0 I by means of a heat treatment. A red dyeing was obv V V H Vtained.

When, in the above Example, the same amount of N:NN=NOHmonofluoro-dichloromethane or 1, l ,2,2-tetrafluorodichloro-ethane wasused instead of trichloro- 25 fluoromethane, almost the same resultswere obtained.

E x A M P L E 13 were dispersed at about 25C in 1 liter of1,2,2-trifiuoro-trichloro-ethane. A staple fiber yarn made frompolyvinyl chloride fibers having high resistance to heat, was paddedwith this dyestuff dispersion on a foulard machine and dried at about50C. Subsequently, the yarn was thermosoled for seconds at a temperatureNH N=N-N=N/ of 130C. An orange brown dyeing was obtained.

0 We claim: 7 U l. A process for the dyeing of a textile material madeNH of fibers of linear aromatic polyester which comprises impregnatingsaid textile material with a dyebath consisting essentially of anorganic dyestuff dissolved or dispersed in a halogenated methane orethane of the formula Two Grams of the dyestuff of the formula (CI. No.26150 Solvent Black 3) were dissolved at about 30C in 1 liter of anazeotropic mixture consisting of 94% of 1,2,2-trifiuorotrichloroethaneand 6% of methanol. A staple fiber fab- R F I'iC made from cellulose 21% acetate fibers was wherein R is CFCI CFCI2, CC|3, 1 v or padded withthis dyebath on a foulard machine and 1 and methylene chloride, andfixing then dried at about 50C. Subseq n ly the p y g said dyestuff onor in said fibers by applying heat to said was treated for 30 seconds at160C, for fixing the dyetextile material. stuff. A grey dyeing wasobtained. 2. A process according to claim 1 wherein said halogenatedmethane or ethane and said methylene chlo- E X A M P L E 14 ride are anazeotropic mixture thereof.

3. A process according to claim 1 wherein said halogenated methane orethane and said methylene chloride are in a weight ratio of 50% to 99%of the former to 50% to 1% of the latter.

Two Grams of the dyestuff of the formula m 4. A process according toclaim 1 wherein said halo- H genated methane or ethane and saidmethylene chlo- N=Nii 1 1 5 5 ride are in a weight ratio of to 99% ofthe former to. 15% to 1% of the latter.

( 5. A process according te claim 1 wherein said textile H3 material isimpregnated with said dyebath in an amount of about 50% to about byweight of said material.

6. A process according to claim 1 wherein said textile (Cl NO 12700Solvent Yellow 16) 60 material is impregnated with said dyebath in anamount were dissolved in 1 liter of l,2,2-trifluoro-trichlorox lgg zzggrz zz z i g' g fi z gijggg 3:2

ehtane' Subsequently this bath was applied by padding bath COEltfllIlSabout 0.152: to about 5% by weight 0 f a on a foulard machine at about40C to a fabric made surface active agent.

from cellulose-triacetate fibers. After the pad-dyeing 65 A processaccording to claim 1 wherein said had been dried in the air, a thermosoltreatment was bath contains about 0.5% to about 1% by weight f 3performed for 30 seconds at C. A yellow dyeing urfa e i e t;

was obtained. 1r 4r

2. A procEss according to claim 1 wherein said halogenated methane orethane and said methylene chloride are an azeotropic mixture thereof. 3.A process according to claim 1 wherein said halogenated methane orethane and said methylene chloride are in a weight ratio of 50% to 99%of the former to 50% to 1% of the latter.
 4. A process according toclaim 1 wherein said halogenated methane or ethane and said methylenechloride are in a weight ratio of 85% to 99% of the former to 15% to 1%of the latter.
 5. A process according te claim 1 wherein said textilematerial is impregnated with said dyebath in an amount of about 50% toabout 150% by weight of said material.
 6. A process according to claim 1wherein said textile material is impregnated with said dyebath in anamount of about 70% to about 90% by weight of said material.
 7. Aprocess according to claim 1 wherein said dyebath contains about 0.1% toabout 5% by weight of a surface active agent.
 8. A process according toclaim 1 wherein said dyebath contains about 0.5% to about 1% by weightof a surface active agent.